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Confused on Constructive/Destructive Interference!
A film with n=1.6 is deposited on glass. What is the thinnest film that will produce constructive interference in the reflection of light with a wavelength of 575 nm?
I have 2 equations that I can choose from...
Constructive Interference for 0 to 2 refl. phase changes
Destructive Interference for 1 refl. phase changes
2T = m * t/n
t = wavelength
Destructive Interference for 0 to 2 refl. phase changes
Constructive Interference for 1 refl. phase changes
2T = (m + 1/2) * t/n
t = wavelength
How do I know which one to use?
I chose the 2nd one because I assumed there was only 1 phase change.
How do figure out what m =?
Homework Statement
A film with n=1.6 is deposited on glass. What is the thinnest film that will produce constructive interference in the reflection of light with a wavelength of 575 nm?
Homework Equations
The Attempt at a Solution
I have 2 equations that I can choose from...
Constructive Interference for 0 to 2 refl. phase changes
Destructive Interference for 1 refl. phase changes
2T = m * t/n
t = wavelength
Destructive Interference for 0 to 2 refl. phase changes
Constructive Interference for 1 refl. phase changes
2T = (m + 1/2) * t/n
t = wavelength
How do I know which one to use?
I chose the 2nd one because I assumed there was only 1 phase change.
How do figure out what m =?